I gotta put down some weed kill next year as my pasture is just getting to over run with weeds. Problem is, my new pond, and fish, are now the recipient of that pasture run off. What's safe to use to kill weeds and not kill or damage fish/pond. Figure I would bring the subject up during winter to noodle on it.

Bumpty. Experts?

What about just cutting the pasture ? If not then what kind of weeds , how far from the pond and what does your water look like in summer (green or clear), and any weeds in the pond? Are you trying to get rid of the grass/weeds (kill it)or not? Lets start with that info.

What kind of weeds do you have? How think are they - do you intend spot treatment or a more nuclear option?

Depending on what type of weeds you are targeting ,Dow makes a product called milestone that we use in Iowa.It can be sprayed next to water.

We cut the field, about 8 acres, once a year, in fall. The pond is about 18 months old, about 11 ft deep, presently.
The water is Chocolete brown, with a lot of suspended clay. When it gets full, going to try and clear it up, but not till then. There are no weeds in the pond, and probably won't be with the depth of the clay. The pond is a circle, about 160 ft by 18 ft deep. What kind of Weeds?, That one I can't answer till I research them darn weeds. The weeds are pushing the native Blue tip grass/straw out, which is my erosion control.
8 acres would be tough to spot spray, so a 25 gallon tank with a 10ft boom would be nice to use.
The field, including the weeds, come right up to the pond.
That Milestone may be the key, I will research it. Most herbicides in Texas need a license to purchase and spray, so let's hope not. Appreciate the help!!

One thing you can try is to leave an unsprayed buffer strip around the pond of about 50 feet. Cut that area and incorporate grass that will blanket the area and not allow weeds to grow through. Spot treat those weeds that come up in it with a selective product that kills weeds but not grass.

Blue tip grass? You talking about Bluestem?

Native Grass

Correct, Bluestem, I believe is the correct term. Pretty strong and provides good erosion control. This field has not been hayed for many years. I like your idea, will provide a berm of 50 ft and spot spray that area. Thanks for the advice

Ken,

I agree 100% with Eric. Heavily overseeding this area in the early springtime should crowd out any weeds. An appropriate pH amendment and fertilizer should also be applied.

As for the other acreage -- I haven't seen anything about critters in this pasture. Are there horses, cattle, goats, sheep, etc., grazing the pasture? If not, I would brush hog this field several times during the season to not allow any of the weeds to go to seed. If you do have critters and the weeds aren't getting grazed, I'd either spot treat or cut before they can go to seed.

I'd also heavily overseed with a good pasture grass or legume appropriate for your area, and lime/fertilize as based on a good soil survey.

If you get good root systems in place in the drainage areas, you should be able to cut the suspended solids considerably.

I'd be very reluctant to start a spraying program, especially until you have solid identification of the weeds you are trying to eliminate, especially with respect to the primary grass you now have in the pasture.

Good luck,
The Other Ken

I asked my sister, who works for J. F. New. She in turn asked the guys at the nursery. They said: "We would need to know what kinds of weeds he has. If they are annual weeds, he can just mow the areas frequently to keep the annuals from re-seeding. If he had tough, perennial weeds, he might be able to use a selective herbicide such as 2-4-D or Plateau."

So, if you can find out what type of weeds they are, she can ask for a more detailed answer.

Assuming that the "weeds" are broadleaves, you are most likely going to end up using 24D or some variation thereof. I don't think there are too many other herbicides that won't kill the grass. There is a variation of 24D that is especially formulated for pastures, however the name escapes me right now.